The maturing thing goes on and on and on until death and maybe even longer.
It gets particularly rough when someone you depended on and thought you knew turns out to have been putting out half-truths for 15 years. I think Shakespeare had it right when he had Polonius say,
This above all: to thine own self be true,
And it must follow, as the night the day,
Thou canst not then be false to any man.
Farewell, my blessing season this in thee!
of course, the trick is in figuring out what it means to be true to yourself when you are being pulled in all directions and heart rules head. So fuck that.